Otago University researchers are calling for elite sports to abandon gender binary divisions, saying it's unfair for trans women to compete with other women.
Since 2015, the International Olympic Committe has allowed male-to-female transgender athletes to compete in the women's division if their testosterone is held below 10nmol/L.
The topic around inclusion of trans women in sport has raised a serious debate and revealed polarising opinions, especially around the recent case of New Zealand weightlifter Laurel Hubbard, a trans woman competing in the 2018 Commonwealth Games.
Otago physiology professor Alison Heather says this is significantly higher than that of cis-gender women, whose sex and gender align as female.
“Science demonstrates that high adult levels of testosterone, as well as permanent testosterone effects on male physiology during in utero and early development, provides a performance advantage in sport and that much of this male physiology is not mitigated by the transition to a transwoman,” she said.
The argument is not that trans women should be excluded from competing overall, but rather there are calls for a third division to be created for trans women and intersex women.
Otago researchers are calling for radical change to what they describe as "the outdated structure of the gender division currently used in elite sport”.
The potential solution includes calculating a handicap for trans women based on their testosterone levels - similar to what's currently used in golf.
Otago researchers' preferred option is an extension of this with a proposed algorithm that could account for a range of parameters, both physical and social, including physiological parameters, gender identity and could include socioeconomic status.
Associate Professor Lynley Anderson the goal is to be both inclusive and fair at the elite level.
"Some innovative thinking is required, rather than attempting to shoehorn people into either ‘male’ or ‘female’."